Radiative rates of transitions from the 2s2p$^{3}$ $^{5}$S{\deg}$_{2}$ level of neutral carbon

Abstract

The measured radiative rates of the 2s22p2 3P1,2 - 2s2p3 5S{\deg}2 intercombination transitions in neutral carbon reported in the literature are critically evaluated by comparing them with theoretical and semi-empirical results. The experimental and theoretical values are compared for the carbon isoelectronic sequence from neutral carbon to nine-times ionized phosphorous. We find strong support for the currently recommended theoretical data on C I and conclude that the published measurements for this transition in neutral carbon cannot be trusted. The reasons for the discrepancies are not clear, and new experiments are needed.